Developing novel improvements to pig nuclear transfer (cloning) procedures will ultimately lead to somatic cell derived cloned pigs. Today's cattle and sheep cloning methods have been largely unsuccessful when applied to pigs. The few cloned pig embryos that have been produced lack the cell numbers needed for further development. Specifically, ProLinia will use Metaphase (M) I instead of MII oocytes as the recipient cytoplasm for synchronized M-phase donor cells, thus improving and extending the nuclear reprogramming capacity of the cloning process. First, methods for obtaining and arresting pig oocytes in MI will be developed. Then the M- phase donor nucleus must form a diploid nuclear transfer embryo, and finally, development rates and cell numbers in these embryos will be compared to interphase donor nuclei derived nuclear transfer embryos. Success in Phase I will lead to efficiently cloned pigs in Phase II. Cloned pigs are an important platform giving rise to better animal models for human diseases and uses in xenotransplantation. Gene knockout pigs facilitated by the cloning process will produce more informative and less variable animal models, and in the xenotransplant field, new sources of organs and cell to treat devastating diseases ranging from heart and kidney disease to Parkinson's disease. PROPOSED COMMERCIAL APPLICATIONS: Nuclear transfer is a platform technology that will be used to produce uniform and genetically modified (gene knockout) pigs for biomedicine. These applications include production of various porcine animal models for human diseases and for xenotransplantation. The use of pigs as organ donors for humans is potentially a $6 billion market. ProLinia will play a niche role in developing xenotransplantation.